China's ever increasing geopolitical penetration of and presence in Africa has attracted much interest. China is not alone in these strategic manoeuvrings. Iran is expanding its economic links to Africa in order to cope with American and European isolation and restrictions on financial dealings. But President Mahmoud Ahmadinejad's trips to Zimbabwe and Uganda last week could reflect two different strategic ambitions of Iran in Africa: circumventing America and Europe's ban on the export to Iran of materials usable in the development of nuclear weapons; and influencing United Nations security council debate on its nuclear programme.

"Be also assured, comrade president Ahmadinejad, of Zimbabwe's continuous support of Iran's just cause on the nuclear issue," Zimbabwe's president, Robert Mugabe, pledged last week. The prospect that Iran had secured exclusive uranium rights in Zimbabwe for its nuclear programme emerged following Mugabe's comments. George Charamba, Mugabe's spokesman, responded by saying that "mining rights had not yet been finalised" and "the Iranians have a peaceful nuclear program. This cannot be said about the Americans who mined uranium in the Democratic Republic of Congo, and went on to produce a nuclear bomb used to attack Japan. We have our uranium and no one is mining it, until we decide otherwise".

Yesterday, contrary to Charamba's assertion that "we have our uranium and no one is mining it", Zimbabwe's industry and commerce minister W Ncube said: "There is no evidence that Zimbabwe has commercial deposits of uranium, so that question [of the Iran uranium deal] does not arise at all."

The contradictory statements coming out of Zimbabwe are fanning international suspicion about the full extent of Iran-Zimbabwe relations.

From Zimbabwe, Ahmadinejad departed for Uganda to conduct nuclear diplomacy with President Yoweri Kaguta Museveni. Ahmadinejad lobbied Uganda, which is currently a non-permanent member of the UN security council, to oppose American-led threats to impose stringent sanctions on Iran over its nuclear programme. Museveni was noncommittal after the meeting, arguing: "We [Uganda] are just students on this matter. It is a debate I have not been following. Now I am going to engage the United States to hear their version, then come back to and consult with our African brothers whom I represent on the UN security council."

Uganda is in a quagmire. It receives considerable aid from the west and Museveni was for a long time America's blue-eyed boy in Africa. Siding with Iran could jeopardise these gains. But if African states support Iran's case that its nuclear programme is a peaceful one, as Zimbabwe is already doing, Uganda will not want to be out of step with African opinion, lest it is interpreted as a western lackey.

Iran's existing nuclear weapons capabilities are nil, but all too often the most unfavourable case assumptions about the country's nuclear ambitions are played up, particularly in America and Israel. Iran is an undemocratic country that violates human rights – but so are many others in the Middle East and on the nuclear weapons-wielding UN security council permanent members' board. Tougher sanctions on Iran are unlikely to yield a meaningful result because of the inherent limitations of this measure, while an American-led military attack could fuel anti-American militancy in the Middle East.

Iran can still be persuaded peacefully to ratify and implement the nuclear proliferation treaty additional protocol, while having allowance to enrich uranium for energy purposes. Iran's machinations in Africa last week have increased western and Israeli mistrust but they must, nonetheless, be treated soberly in case the crescendo of alarm at Iran's nuclear ambitions is amplified. Iran, though, must not disregard the imperative nature of being forthcoming in negotiations.